<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>html,css,javascript实例</title>
		<style type="text/css">
			body{
				background-image:url(img/1-4-1-2.jpg);
				background-attachment:scroll;
				background-position:100% 100%;
				background-repeat:no-repeat;
			}
		</style>
		
		<FORM name="Keypad" action="">
		<TABLE>
		<B>
		<TABLE border=2 width=50 height=60 cellpadding=1 cellspacing=5>
		<TR>
		<TD colspan=3 align=middle>
		<input name="ReadOut" type="Text" size=24 value="0" width=100%>
		</TD>
		<TD>
		</TD>
		<TD>
		<input name="btnClear" type="Button" value="  C  " onclick="Clear()">
		</TD>
		<TD><input name="btnClearEntry" type="Button" value="  CE " onclick="ClearEntry()">
		</TD>
		</TR>
		<TR>
		<TD>
		<input name="btnSeven" type="Button" value="  7  " onclick="NumPressed(7)">
		</TD>
		<TD>
		<input name="btnEight" type="Button" value="  8  " onclick="NumPressed(8)">
		</TD>
		<TD>
		<input name="btnNine" type="Button" value="  9  " onclick="NumPressed(9)">
		</TD>
		<TD>
		</TD>
		<TD>
		<input name="btnNeg" type="Button" value=" +/- " onclick="Neg()">
		</TD>
		<TD>
		<input name="btnPercent" type="Button" value="  % " onclick="Percent()">
		</TD>
		</TR>
		<TR>
		<TD>
		<input name="btnFour" type="Button" value="  4  " onclick="NumPressed(4)">
		</TD>
		<TD>
		<input name="btnFive" type="Button" value="  5  " onclick="NumPressed(5)">
		</TD>
		<TD>
		<input name="btnSix" type="Button" value="  6  " onclick="NumPressed(6)">
		</TD>
		<TD>
		</TD>
		<TD align=middle><input name="btnPlus" type="Button" value="  +  " onclick="Operation('+')">
		</TD>
		<TD align=middle><input name="btnMinus" type="Button" value="   -   " onclick="Operation('-')">
		</TD>
		</TR>
		<TR>
		<TD>
		<input name="btnOne" type="Button" value="  1  " onclick="NumPressed(1)">
		</TD>
		<TD>
		<input name="btnTwo" type="Button" value="  2  " onclick="NumPressed(2)">
		</TD>
		<TD>
		<input name="btnThree" type="Button" value="  3  " onclick="NumPressed(3)">
		</TD>
		<TD>
		</TD>
		<TD align=middle><input name="btnMultiply" type="Button" value="  *  " onclick="Operation('*')">
		</TD>
		<TD align=middle><input name="btnDivide" type="Button" value="   /   " onclick="Operation('/')">
		</TD>
		</TR>
		<TR>
		<TD>
		<input name="btnZero" type="Button" value="  0  " onclick="NumPressed(0)">
		</TD>
		<TD>
		<input name="btnDecimal" type="Button" value="   .  " onclick="Decimal()">
		</TD>
		<TD colspan=3>
		</TD>
		<TD>
		<input name="btnEquals" type="Button" value="  =  " onclick="Operation('=')">
		</TD>
		</TR>
		</TABLE>
		</TABLE>
		</B>
		</FORM>
		</CENTER>
		<SCRIPT LANGUAGE="JavaScript">
		<!-- Begin
		var FKeyPad = document.Keypad;
		var Accum = 0;
		var FlagNewNum = false;
		var PendingOp = "";
		function NumPressed (Num) {
		if (FlagNewNum) {
		FKeyPad.ReadOut.value  = Num;
		FlagNewNum = false;
		   }
		else {
		if (FKeyPad.ReadOut.value == "0")
		FKeyPad.ReadOut.value = Num;
		else
		FKeyPad.ReadOut.value += Num;
		   }
		}
		function Operation (Op) {
		var Readout = FKeyPad.ReadOut.value;
		if (FlagNewNum && PendingOp != "=");
		else
		{
		FlagNewNum = true;
		if ( '+' == PendingOp )
		Accum += parseFloat(Readout);
		else if ( '-' == PendingOp )
		Accum -= parseFloat(Readout);
		else if ( '/' == PendingOp )
		Accum /= parseFloat(Readout);
		else if ( '*' == PendingOp )
		Accum *= parseFloat(Readout);
		else
		Accum = parseFloat(Readout);
		FKeyPad.ReadOut.value = Accum;
		PendingOp = Op;
		   }
		}
		function Decimal () {
		var curReadOut = FKeyPad.ReadOut.value;
		if (FlagNewNum) {
		curReadOut = "0.";
		FlagNewNum = false;
		   }
		else
		{
		if (curReadOut.indexOf(".") == -1)
		curReadOut += ".";
		   }
		FKeyPad.ReadOut.value = curReadOut;
		}
		function ClearEntry () {
		FKeyPad.ReadOut.value = "0";
		FlagNewNum = true;
		}
		function Clear () {
		Accum = 0;
		PendingOp = "";
		ClearEntry();
		}
		function Neg () {
		FKeyPad.ReadOut.value = parseFloat(FKeyPad.ReadOut.value) * -1;
		}
		function Percent () {
		FKeyPad.ReadOut.value = (parseFloat(FKeyPad.ReadOut.value) / 100) * parseFloat(Accum);
		}
		// End -->
		</SCRIPT>  
	</head>

	<body>
		<center>
			<h2>第一个html,css,javascript实例</h2>
		</center>
		<hr />
		<p class="p1">1.HTML是网页架构基础</p>	
		<p class="p1">2.用CSS定义背景图片的位置，标题2和段落的格式</p>
		<p class="p1">3.用Javascript编写计算器</p>
	</body>
</html>
